Alcohol-chlordiazepoxide interaction.

The effects of chlordiazepoxide (CDP) or its N-demethyl metabolite (NDCDP) on ethanol-induced sleep time were investigated. The results indicate that CDP or NDCDP produced a supra-additive effect on the duration of sleep time induced by ethanol. These effects were not due to an alteration in the rate of elimination of blood ethanol levels. Mice which were administered CDP/ethanol had significantly higher blood and brain CDP levels than mice injected with CDP alone. The increase in CDP concentrations could be partly responsible for the supra-additive prolongation of ethanol sleep time. Our results also indicate that NDCDP and/or its metabolites were largely responsible for the supra-additive effect, because mice injected with CDP/ethanol or NDCDP/ethanol (ethanol 4 g/kg: CDP or NDCDP, 10 mg/kg) showed comparable increases in sleep time, and the blood and brain levels of NDCDP were comparable in these two groups.